Section milling tool, methods and system

ABSTRACT

A section milling tool includes an electrically operated section mill configured to mill without conveying swarf to surface, an electric motor operably connected to the section mill, an electric stroker operably connected to the motor, and an electric anchor operably connected to the stroker. A method for section milling a downhole structure without conveying swarf to surface includes running a bottom hole assembly (BHA) on a wireline, deploying an anchor, rotating a section mill, and stroking the section mill with a stroker. A method for reducing emissions during a section milling operation includes running a tool on wireline, and milling a tubular structure in the borehole. A method for plugging and abandonment of a well includes running a tool on wireline, milling a tubular structure in the borehole, and plugging the well at the milled tubular structure.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of an earlier filing date from U.S. Provisional Application Ser. No. 63/336,074 filed Apr. 28, 2022, the entire disclosure of which is incorporated herein by reference.

BACKGROUND

In the resource recovery and fluid sequestration industries section milling is needed for various operations including plug and abandonment operations. It is a ubiquitous operation and requires the use of a rig to run a bottom hole assembly on pipe. Such operations are costly in time and equipment. The art is always receptive to teachings that reduce cost and improve efficiency.

SUMMARY

An embodiment of a section milling tool, including an electrically operated section mill configured to mill without conveying swarf to surface, during use, an electric motor operably connected to the section mill, an electric stroker operably connected to the motor, and an electric anchor operably connected to the stroker.

An embodiment of a method for section milling a downhole structure without conveying swarf to surface, including running a bottom hole assembly (BHA) on a wireline, deploying an anchor to prevent both longitudinal and rotational movement of the BHA relative to the wireline and the structure, rotating a section mill and milling a tubular structure, and stroking the section mill with a stroker.

An embodiment of a method for reducing emissions during a section milling operation, including running a tool into a borehole on wireline and without a rig, and milling a tubular structure in the borehole.

An embodiment of a method for plugging and abandonment of a well, including running a tool into a borehole on wireline and without a rig, milling a tubular structure in the borehole, and plugging the well at the milled tubular structure.

An embodiment of a borehole system including a borehole in a subsurface formation, a tubular structure in the borehole, and a tool disposed within the tubular structure.

BRIEF DESCRIPTION OF THE DRAWINGS

The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:

FIG. 1 is a schematic view of a section milling tool in a borehole; and

FIG. 2 is a schematic view of a borehole system including the section milling tool illustrated in FIG. 1 .

DETAILED DESCRIPTION

A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.

Referring to FIG. 1 , a section milling tool 10 is illustrated in a borehole 12 having a tubular structure 14 therein requiring milling. The milling operation may be for any particular need. One example of a need would be fore a plug and abandonment operation. The tool 10 may be characterized as a bottom hole assembly (BHA) and so may be referred to as tool or BHA herein. Tool 10 is run on a wireline 16 and accordingly no rig is required to run the tool. The absence of a rig means cost savings, time savings, reduced emissions with regard to moving the rig into place, etc. Pursuant to the wireline operation, the various components of the tool 10, including an anchor 18, a stroker 20, a motor 22, and a section mill 24 are electrically controlled and driven. Each of these components individually are found in other tools and are commercially available.

For example, the anchor 18 may be a tractor known under the trademark PowerTrac™ Tractor System, commercially available from Baker Hughes; the stroker 20 is a axial movement tool such as a PRIME™ Stroker, commercially available from Baker Hughes; the motor 22 is a rotational movement tool, an example being a Direct Drive Rotation™ rotational tool, commercially available from Baker Hughes; and the section mill is a milling/cutting tool such as a Heavy Metal™ Section Mill System, commercially available from Baker Hughes. These components have not however been used together before nor has any section mill configuration been run on wireline 16. The tool 10 will also have a connector and casing collar locator 26 for connection to the wireline 16 and for determination of depth.

The section mill 24 is configured to avoid the conveyance of swarf uphole and hence is an additional reason that a rig is not needed with the tool 10. Avoidance of Swarf conveyed to surface reduces the need for swarf treatment, reduces risks that swarf presents to equipment, and reduces risks posed to the environment.

Tool 10 as described enables a method for section milling a downhole structure without conveying swarf to surface that is of great value to the art in view of the positive results set forth hereinabove. The tool 10 is run on wireline to a target location in the borehole 12 where the tubular structure 14 such as a casing of tubing segment is in need of milling for various reasons, including plug and abandon operations. Once the tool 10 arrives at the selected target location, the anchor 18 is electrically actuated to engage the tubular structure 14 and thereby retrain movement of the tool 10 longitudinally of rotationally of the tubular structure 14. In other words, with the anchor 18 set, the tool 10 may not move with respect to the tubular structure 14. At this point the stroker 20 needs to be at its extended position and may either be left alone if it is there or be electrically stroked to get it there, if it is not there already. The section mill 24 is actuated electrically to move cutters 28 thereof into the appropriate active position and the motor 22 is electrically driven to rotate the section mill 24 relative to anchor 18 and hence the tubular structure 14. During the electric rotation of section mill 24, tubular structure 14 is milled. Further, due to stroking of the stroker 20, the mill 24 will get closer to the anchor 18 while milling to mill a window as it moves toward anchor 18. The swarf created by the mill 24 is jettisoned downhole and need not be conveyed to surface. If the window needed is longer than stroke length of the stroker 20, the anchor is electrically unset, the stroker 20 is extended while the wireline 16 is drawn uphole, and the anchor reset. Then the motor may be restarted and the mill 24 drawn again toward the anchor 18, lengthening the window. This procedure may be repeated any desired number of times with increasing lengthening of the resulting window.

After milling the window, cement may be pumped to location to create a cement plug that extends to the rock of the borehole 12 rather than to an inside of the tubular structure 14 and hence avoid any annulus area requiring further treatment. The well would then be ready for abandonment.

Another method enabled by the disclosure hereof is a method for reducing emissions during a section milling operation. Due to the running of the tool 10 on wireline into the borehole and without the rig, emissions are reduced to the benefit of the planet. And though the rig is not present, the method includes milling the tubular structure 14 in the borehole 12.

Referring to FIG. 2 , a borehole system 30 is illustrated. The system 30 comprises a borehole 32 in a subsurface formation 34. A string 36 is disposed within the borehole 32. The tool 10 is disposed within or as a part of the string 36 disclosed herein.

Set forth below are some embodiments of the foregoing disclosure:

Embodiment 1: A section milling tool, including an electrically operated section mill configured to mill without conveying swarf to surface, during use, an electric motor operably connected to the section mill, an electric stroker operably connected to the motor, and an electric anchor operably connected to the stroker.

Embodiment 2: The tool as in any prior embodiment, further comprising a wireline interface operably connected to the anchor.

Embodiment 3: The tool as in any prior embodiment, wherein the anchor inhibits both longitudinal and rotational movement, when set.

Embodiment 4: The tool as in any prior embodiment, wherein the stroker pulls the mill toward the anchor, when in use.

Embodiment 5: The tool as in any prior embodiment, wherein the mill is configured to jettison swarf in a downhole direction of the mill while cutting in an uphole direction, during use.

Embodiment 6: A method for section milling a downhole structure without conveying swarf to surface, including running a bottom hole assembly (BHA) on a wireline, deploying an anchor to prevent both longitudinal and rotational movement of the BHA relative to the wireline and the structure, rotating a section mill and milling a tubular structure, and stroking the section mill with a stroker.

Embodiment 7: The method as in any prior embodiment, wherein the deploying is electrically deploying.

Embodiment 8: The method as in any prior embodiment, wherein the rotating is electrically rotating against the anchor.

Embodiment 9: The method as in any prior embodiment, wherein the milling includes jettisoning swarf from the milling in a downhole direction relative to the mill.

Embodiment 10: The method as in any prior embodiment, wherein the stroking is moving the mill toward the anchor and in an uphole direction.

Embodiment 11: The method as in any prior embodiment, wherein the stroking is electrical stroking.

Embodiment 12: The method as in any prior embodiment, further including releasing the anchor.

Embodiment 13: The method as in any prior embodiment, further including moving the BHA, resetting the stroker and the anchor, and milling an additional section of tubular structure.

Embodiment 14: A method for reducing emissions during a section milling operation, including running a tool as in any prior embodiment into a borehole on wireline and without a rig, and milling a tubular structure in the borehole.

Embodiment 15: A method for plugging and abandonment of a well, including running a tool as in any prior embodiment into a borehole on wireline and without a rig, milling a tubular structure in the borehole, and plugging the well at the milled tubular structure.

Embodiment 16: A borehole system including a borehole in a subsurface formation, a tubular structure in the borehole, and a tool as in any prior embodiment disposed within the tubular structure.

The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Further, it should be noted that the terms “first,” “second,” and the like herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The terms “about”, “substantially” and “generally” are intended to include the degree of error associated with measurement of the particular quantity based upon the equipment available at the time of filing the application. For example, “about” and/or “substantially” and/or “generally” can include a range of ±8% a given value.

The teachings of the present disclosure may be used in a variety of well operations. These operations may involve using one or more treatment agents to treat a formation, the fluids resident in a formation, a borehole, and/or equipment in the borehole, such as production tubing. The treatment agents may be in the form of liquids, gases, solids, semi-solids, and mixtures thereof. Illustrative treatment agents include, but are not limited to, fracturing fluids, acids, steam, water, brine, anti-corrosion agents, cement, permeability modifiers, drilling muds, emulsifiers, demulsifiers, tracers, flow improvers etc. Illustrative well operations include, but are not limited to, hydraulic fracturing, stimulation, tracer injection, cleaning, acidizing, steam injection, water flooding, cementing, etc.

While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited. 

What is claimed is:
 1. A section milling tool, comprising: an electrically operated section mill configured to mill without conveying swarf to surface, during use; an electric motor operably connected to the section mill; an electric stroker operably connected to the motor; and an electric anchor operably connected to the stroker.
 2. The tool as claimed in claim 1, further comprising a wireline interface operably connected to the anchor.
 3. The tool as claimed in claim 1, wherein the anchor inhibits both longitudinal and rotational movement, when set.
 4. The tool as claimed in claim 1, wherein the stroker pulls the mill toward the anchor, when in use.
 5. The tool as claimed in claim 1, wherein the mill is configured to jettison swarf in a downhole direction of the mill while cutting in an uphole direction, during use.
 6. A method for section milling a downhole structure without conveying swarf to surface, comprising: running a bottom hole assembly (BHA) on a wireline; deploying an anchor to prevent both longitudinal and rotational movement of the BHA relative to the wireline and the structure; rotating a section mill and milling a tubular structure; and stroking the section mill with a stroker.
 7. The method as claimed in claim 6, wherein the deploying is electrically deploying.
 8. The method as claimed in claim 6, wherein the rotating is electrically rotating against the anchor.
 9. The method as claimed in claim 6, wherein the milling includes jettisoning swarf from the milling in a downhole direction relative to the mill.
 10. The method as claimed in claim 6, wherein the stroking is moving the mill toward the anchor and in an uphole direction.
 11. The method as claimed in claim 6, wherein the stroking is electrical stroking.
 12. The method as claimed in claim 6, further including releasing the anchor.
 13. The method as claimed in claim 6, further including moving the BHA, resetting the stroker and the anchor, and milling an additional section of tubular structure.
 14. A method for reducing emissions during a section milling operation, comprising: running a tool as claimed in claim 1 into a borehole on wireline and without a rig; and milling a tubular structure in the borehole.
 15. A method for plugging and abandonment of a well, comprising: running a tool as claimed in claim 1 into a borehole on wireline and without a rig; milling a tubular structure in the borehole; and plugging the well at the milled tubular structure.
 16. A borehole system comprising: a borehole in a subsurface formation; a tubular structure in the borehole; and a tool as claimed in claim 1 disposed within the tubular structure. 